George armes tower



(No Model.)

" G. A. TOW

SEEED AND DIREGTIO DICATOR.

No. 564,168. Patented July 14, 1896.

avwewtox I M SH'OZ'HGIJJ ms mam no WASHINGYON u c UNIT D STATES PATENT OFFICE.

GEORGE ARMES TOWER, OF RICHMOND, VIRGINIA, ASSIGNOR OF ON E-IIALF TO GEORGE R. JARMAN, OF SAME PLACE.

SPEED AND DIRECTION INDICATOR.

SPECIFICATION forming part of Letters Patent No. 564,168, dated July 14, 1896.

Application filed March 21,1896. erial No. 584,305. (No model.)

To all whom it may concern.-

Be it known that I, GEORGE ARMES TOWER, a citizen of the United States, residing at Richmond, in the county of Henrico and State of Virginia, have invented certain new and useful Improvements in Speed and Direction Indicators, of which the following is a specification, reference being had therein to the accompanying drawings.

This invention is designed to provide a very simple electrical device for automatically indicating both the speed and the direction of rotary shafts, it being especially adapted for use on shipboard to positively indicate in the pilot-house or elsewhere the direction in which the propeller or screw is turning, as well as the speed of the same, thus keeping the pilot constantly informed, without the aid of the usual unreliable signals, and enabling him to maneuver the vessel with greater safety and exactitude.

Although the form of the device shown and described herein is the one I prefer at present, I do not desire to restrict myself in this respect, as other forms, it is obvious, may be devised without departing from the spirit of the invention.

In the drawings, Figure 1 is a perspective view of one form of the indicator; Fig. 2, a cross-section of the shaft, showing the automatic circuit-closing device; and Fig. 3, a plan view of the same.

Referring to the drawings by numerals, 1 designates a hub of suitable insulating material, which is preferably constructed of two halves, secured rigidly to the propeller-shaft by two suitable annular clamps 2, and is provided with two annular grooves or Ways 3. Embedded in the outer surface of this hub is a longitudinal contact-plate 4, which extends across the two annular grooves and is let into the hub deep enough to bring its surface flush with the bottom of the grooves. Resting loosely in each of the annular grooves is a metal ring 5, which is larger in diameter than the hub at the bottom of the grooves, to permit its lower portion to swing away from the bottom of the grooves. In fact, these rings merely embrace and hang loosely on the hub, the grooves serving simply to hold them in place, the shaft and hub being thereby permitted to freely rotate independently of the rings. By this arrangement, as will be seen most clearly in Fig. 2, the embedded contactplate will, at every revolution of the hub, electrically connect the rings at the point where they rest on the hub. Each ring is provided with two contact-fingers 6, one projecting radially from each side of the ring on opposite sides of the hub. Under each of these 6c contacts is arranged a mercury-cup 7 or other contact device, these cups being arranged so that when the two fingers 011 either side dip into their respective cups the fingers on the opposite side will be held up out of electrical contact with their cups, as shown in Fig. 2. There are two independent electrical circuits, the two cups on one side being in one of them and the cups on the other side being in the other, so that when the fingers on either side dip into their cups and the rotary contactplate t connects the rings'the circuit on that side will be closed.

The indicating device that is to be located in the pilot-house may be of various forms, but I prefer that form shown at the top of Fig. 1. This form consists of a suitable faceplate provided with a pair of openings 8, one opening being to indicate the backward and the other the forward motion of the propeller. 8o Arranged behind each opening is a Vibrating arm 9, connected to an armature 10, each of the armatures being controlled by an independent electromagnet, and the magnets being respectively in the electrical circuits here- 8 5 inbefore mentioned. By suitable means the vibrating arms are respectively held normally away from their respective openings and are thrown into view only when the magnets are energized.

The operation will be obvious. WVhen the propeller-shaft rotates, it will, by friction, carry the rings over in the direction of its rotation far enough to cause them to dip one pair of their contact-fingers into the adjacent cups and hold them therein. Then at each rotation of the shaft the contact-plate in the hub momentarily closes the circuit on that side and thereby energizes the corresponding magnet in the pilot-house and causes its vibrating arm to swing into viewat the adjacent openings, and the continuous rotation of the shaft in the same direction will cause the same arm to intermittently vibrate or oscillate into view at its opening,-making one vibration for each revolution of the shaft. IVhen the shaft is rotated in the opposite direction, the same operation takes place in the other circuit. Thus by watching the open ings in the face of the indicator the pilot may at all times know in which direction the propeller is turning, and by timing the vibrations he may learn its speed. In this way a perfectly reliable indicator is obtained which will do its work automatically, thereby doing away with the usual unreliable signalsbetween the engineer and the pilot, the misunderstanding of which has often resulted in serious accidents.

In case it is desired to have audible signals or indicators in addition to the visual indicators or in lieu thereof, itis evident that an ordinary sin gle-stroke electric bell may be arranged in each circuit, the bells being different in tone, so that the pilot may readily distinguish between them. One way of carrying out this idea is shown in Fig. 1, in which the bells are shown secured to the casing above the openings, so as to be struck at each vibration of the armature.

It will be observed that an essential fea ture of this invention lies in the use of two circuits and indicators and the peculiar arrangement of the automatic circuit-closing devices, these latter being adapted to be shifted into the circuit being used and to intermittently close the same.

Instead of bells of different tones, it is evident that it is equally feasible to have the bells of the same tone and put a double clapper on one of them, as shown in Fig. 1, so that one hell will give a single stroke and the other will give a double stroke.

It will also be understood that the bells may be dispensed with and luminous shutters employed.

Having thus fully described my invention, what I claim, and desire to secure by Letters Patent, is

1. In a combined direction and speed indicater for rotary shafts, the combination of two electrical circuits, a suitable indicating device in each circuit, a part adapted to be shifted into one circuit by the rotation of the shaft in one direction and into the other by its rotation in the opposite direction and form a part of the circuit into which it for the time being remains, and a device for intermittently closing the circuit into which said part is shifted, substantially as described and for the purpose set forth.

2. In a combined direction and speed indicator for rotary shafts, the combination of two electrical circuits, a suitable indicating device in each circuit, an oscillating part supported 011 said shaft and adapted to be shifted into one circuit by the rotation of the shaft in. one direction and into the other by its rotation in the opposite direction, and a device for intermittently closing the circuit into which said part is shifted, substantially as described and for the purpose set forth.

3. In a combined direction and speed indicater for rotary shafts, the combination of two electrical circuits, a suitable indicating device in each circuit, a pair of loose oscillating parts supported on the shaft, adapted to be shifted into one circuit by the rotation of the shaft in one direction and into the other by its rotation in the opposite dirccs tion,an insulating medium forsaid parts, and a device for intermittently closing the circuit into which said parts are shifted, substantially as described and for the purpose set forth.

at. In a combined direction and speed indicator, the combination of an insulating-hub on the shaft, a pair of oscillating rings sup ported in ways on said hub amtprovidcd with projecting contact-fingers, a contactplate carried by said insulating-hub, two independent circuits, an indicator in each circuit, and mercury-cups adapted to receive said contact-fingers, as and for the purpose set forth.

In testimony whereof I affix my signature in presence of two witnesses.

GEORG E ARMEJ TOlVER.

\Vitnesses:

Gno. R. JARMAN, R. B. Bown. 

